Real-time monitoring large-segment steel truss girder field weighing method and system

Abstract

The invention discloses a real-time monitoring large-section steel truss girder on-site weighing method and system, and relates to the field of bridge construction.The large-section steel truss girder on-site weighing method comprises the steps that a plurality of jacks located on the periphery of the bottom of a steel truss girder section are controlled to conduct multiple times of synchronous lifting, and during each time of synchronous lifting, each time of synchronous lifting is completed; and collecting and calculating attitude parameters of the steel truss girder section, controlling and adjusting the attitude of the steel truss girder section according to a calculation result, and after the attitude parameters are within an allowable deviation range, carrying out next synchronous lifting until the steel truss girder section is lifted to a preset height, and the jack is synchronously unloaded for multiple times until the weight of the steel truss girder section falls on the pressure sensor, so that the steel truss girder section is weighed. And the jacks are synchronously unloaded for multiple times until the weight of the steel truss girder segments falls on the pressure sensors, weighing of the steel truss girder segments is achieved, and according to the weighing method, on the premise that the weighing accuracy and safety are guaranteed, the weighing complexity can be reduced, and the construction cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of bridge construction, specifically to a method and system for real-time monitoring of on-site weighing of large-segment steel truss girders. Background Technology

[0002] In the construction of long-span bridges, a reasonable bridge alignment is crucial in design and construction, playing a decisive role in the bridge's safety and stability. However, in actual construction, the final bridge alignment of long-span bridges is prone to significant deviations from the design alignment, especially for railway bridges. Alignment deviations can prevent the achievement of the original track alignment, causing track laying difficulties and affecting ride comfort and safety. Numerous factors influence the final bridge alignment, including: main girder weight error, alignment errors during cable erection, and construction errors during main girder erection. Among these, the main girder weight deviation is a critical parameter in alignment calculations, playing a vital role in structural safety, load effects, construction accuracy, and cable length adjustments. After determining the weight deviation, the corrected actual weight is used to recalculate the final bridge alignment. Adjustments are then made, such as adjusting cable lengths, to ensure successful closure of the steel beams and that the final bridge alignment meets design requirements. Therefore, determining the main girder weight deviation is of paramount importance.

[0003] Currently, for large-segment steel beams, the weighing process is generally carried out at the steel beam yard, using heavy-duty lifting equipment to measure the weight of the beam segment. However, some long-span bridges are built in mountainous canyons with steep terrain and limited space, making it impossible to transport steel beams in whole segments. Instead, individual beams are transported to the bridge site and assembled on-site into complete truss segments. Simply summing the weights of each component to obtain the total weight of the truss segment is not only cumbersome but also introduces errors, such as neglecting the weight of high-strength bolts, paint, and some ancillary facilities. Measuring the weight of the steel beam in such cases is quite difficult. Furthermore, large-segment steel truss beams are large in size and can weigh hundreds of tons. Using the method of lifting entire segments to obtain their weight is difficult to implement, has large measurement errors, high lifting equipment costs, and poses high safety risks. Summary of the Invention

[0004] This application provides a real-time monitoring method and system for on-site weighing of large-segment steel truss girders. It can solve the technical problems in the prior art where the weight of steel truss girders needs to be accurately controlled in order to ensure the bridge's final alignment. However, when constructing in mountainous canyons, the site is small, and the large-segment steel truss girders are large in size and can weigh hundreds of tons. If the weight is obtained by lifting the entire segment, the implementation process is difficult, the measurement error is large, the lifting equipment cost is high, and the safety risks are high.

[0005] In a first aspect, embodiments of this application provide a method for real-time monitoring of on-site weighing of large-segment steel truss girders, including: Multiple jacks located around the bottom of the steel truss segment are controlled to perform multiple synchronous lifts. During each synchronous lift, the attitude parameters of the steel truss segment are collected and calculated. Based on the calculation results, the attitude of the steel truss segment is controlled and adjusted to ensure that the attitude parameters are within the allowable deviation range before the next synchronous lift is performed. This process continues until the steel truss segment is lifted to the predetermined height. During each synchronous lift, if the attitude parameter deviation exceeds the preset alarm threshold range, an automatic warning is issued and the lifting action is stopped. A pressure sensor is placed at the bottom of the steel truss segment, and the jacks are unloaded synchronously multiple times until the weight of the steel truss segment falls onto the pressure sensor, thus achieving the weighing of the steel truss segment. The attitude parameters are the height difference between the four apex corners of the steel truss segment and the inclination angle between adjacent and opposite measuring points. Measuring points are provided at the same bolt holes at the ends of the four lower chord members of the steel truss segment.

[0006] In conjunction with the first aspect, in one implementation, controlling multiple jacks located around the bottom of the steel truss girder segment to perform multiple synchronized lifting operations specifically includes: Jacks are placed around the bottom of the steel truss girder segment, and an intelligent hydraulic pump station connected to the jack cylinders is installed. An auxiliary support is installed on one side of each jack; Based on the predetermined height of the steel truss girder segment, the synchronous lifting height of each jack is preset; The intelligent hydraulic pump station controls multiple jacks to perform multiple synchronous lifting operations at a preset synchronous lifting height. After each synchronous lifting operation, the thickness of the padding at the top of the auxiliary pier is increased to support the steel truss girder segment.

[0007] In one embodiment, before controlling multiple jacks to perform multiple simultaneous lifting operations at a preset synchronous lifting height, the method further includes: Place a pad on top of each jack; The intelligent hydraulic pump station controls multiple jacks to perform pre-lifting simultaneously to eliminate lifting gaps.

[0008] In one implementation, during each synchronous lifting operation, the attitude parameters of the steel truss girder segments are collected and calculated, specifically including: Two target balls were set as measuring points at the same bolt holes at the ends of the four lower chords of the steel truss girder segment, and a total station with automatic aiming function was placed at the set position. During each synchronous lifting, the total station automatically collects the current spatial coordinates of all measuring points. The coordinate system of the measuring points is established based on the steel truss segment after the pre-lifting is completed. The current spatial coordinates of all measuring points are transmitted to the pre-configured main control unit. Based on the current spatial coordinates of all measuring points, the main control unit calculates the height difference between the ends of the four lower chords of the steel truss segment, as well as the inclination angle between adjacent and opposite measuring points, and obtains the attitude parameters of the steel truss segment.

[0009] In one implementation, the height difference between the four lower chord ends of a steel truss segment is calculated as follows: , , , .

[0010] The four measuring points are, in order, the first measuring point, the second measuring point, the third measuring point, and the fourth measuring point. This indicates the current spatial coordinates of the first measuring point during synchronous lifting. This indicates the current spatial coordinates of the second measuring point during synchronous lifting. This indicates the current spatial coordinates of the third measuring point during synchronous lifting. This indicates the current spatial coordinates of the fourth measuring point during synchronous lifting. The elevation difference between the first and second measuring points. The elevation difference between the second and third measuring points. The elevation difference between the third and fourth measuring points. This represents the elevation difference between the first and fourth measuring points.

[0011] In one implementation, the inclination angle between adjacent and opposite measuring points of a steel truss segment is calculated as follows:

[0012]

[0013]

[0014]

[0015] in, The angle between the first and second measuring points. The angle between the first and third measuring points. The angle between the second and fourth measuring points. The angle between the second and third measuring points is denoted as α.

[0016] In one embodiment, the posture of the steel truss segment is controlled and adjusted according to the calculation results to ensure that the posture parameters are within the allowable deviation range before the next synchronous lifting is performed. During each synchronous lifting, if the posture parameter deviation exceeds a preset alarm threshold, an automatic warning is issued and the lifting action is stopped. The specific steps for determining whether to perform the next synchronous lifting and whether to issue an automatic warning and stop the lifting action include: Based on the truss height, truss width, and segment length of the steel truss segment, determine the set range of the attitude parameters and the alarm threshold range of the steel truss segment; During the end of each synchronous lifting operation, the attitude parameters of the steel truss girder segment are calculated, and the following is determined: If the calculated attitude parameters of the steel truss segment are within the set range, then proceed with the next synchronous lifting. If the calculated attitude parameters of the steel truss segment are not within the set value range and are not within the alarm threshold range, the lifting height of each jack will be adjusted accordingly, and the attitude parameters of the steel truss segment will be calculated again until the calculated attitude parameters of the steel truss segment are within the set value range, and then the next synchronous lifting will be performed. If the attitude parameters of the steel truss segment calculated at the moment are within the alarm threshold range, a warning message will be issued and the lifting action will be stopped.

[0017] In one embodiment, placing the pressure sensor at the bottom of the steel truss segment and repeatedly unloading the jacks synchronously until the weight of the steel truss segment falls onto the pressure sensor, thereby achieving the weighing of the steel truss segment, specifically includes: Several pressure sensors are placed at predetermined positions at the bottom of the steel truss girder segment; Multiple pressure sensors are leveled using a level instrument, and limiting devices are installed on the top surface of the pressure sensors. The jacks and auxiliary piers are alternately used to unload multiple jacks in stages and simultaneously until the weight of the steel truss segment falls on the pressure sensor, and the pressure sensor reading is recorded. Rotate the pressure sensor around its axis to different angles and record the pressure sensor readings at each angle. The weight of the steel truss segment is obtained by calculating the average pressure based on multiple readings from the pressure sensor.

[0018] Secondly, embodiments of this application provide a field weighing system for large-segment steel truss girders, used to implement the above-mentioned field weighing method for large-segment steel truss girders, the field weighing system for large-segment steel truss girders comprising: The lifting unit includes several jacks that are placed around the bottom of the steel truss girder segment for multiple synchronous lifting operations, and an intelligent hydraulic pump station connected to the jack cylinders to control the lifting status of the jacks. The monitoring unit includes a total station for acquiring the current spatial coordinates of the measuring points; A pressure sensor is used to place at the bottom of the steel truss segment after it has been lifted to a predetermined height; The main control unit is used to calculate the attitude parameters of the steel truss segment after each synchronous lifting based on the current spatial coordinates of the measuring point obtained by the total station, and to control the steel truss segment to perform the next synchronous lifting when the attitude parameters are within the allowable deviation range, until the steel truss segment is lifted to the predetermined height. After the steel truss segment is lifted to the predetermined height, the jacks are unloaded synchronously multiple times until the weight of the steel truss segment falls on the pressure sensor, thereby realizing the weighing of the steel truss segment.

[0019] In conjunction with the second aspect, in one embodiment, the main control unit includes a host control computer and a display for displaying data parameters.

[0020] The beneficial effects of the technical solutions provided in this application include: Multiple jacks lift the steel truss segment to the predetermined height in a synchronized manner, facilitating the placement of pressure sensors. Combined with measuring points set at the ends of the four lower chords of the steel truss segment, the attitude parameters of the steel truss segment can be accurately grasped. This ensures the smooth lifting and lowering of the steel truss segment, guarantees the safety of weighing, and keeps the steel truss segment in the correct posture at all times. Even in mountainous areas with uneven terrain, the weighing accuracy can be guaranteed. The weighing process can be carried out on the existing platform without occupying additional space or requiring back-and-forth hoisting and transportation. The weighing and lifting process is achieved by the synchronous movement of the jacks, which greatly reduces the tediousness of weighing work, reduces the use of large hoisting equipment, reduces capital investment, and the weighing process is simple and quick, which can also improve construction efficiency. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 A schematic diagram of a real-time monitoring method for on-site weighing of large-segment steel truss girders provided in this application; Figure 2 A top view of a steel truss segment in a real-time monitoring on-site weighing method for large steel truss segments provided in this application; Figure 3 A schematic diagram of the positions of jacks and auxiliary piers in a real-time monitoring on-site weighing method for large-segment steel trusses provided in this application; Figure 4 This is a schematic diagram showing the placement of pressure sensors in a real-time monitoring method for on-site weighing of large-segment steel trusses provided in this application.

[0023] In the diagram: 1. Steel truss segment; 2. Jack; 3. Measuring point; 4. Intelligent hydraulic pump station; 5. Auxiliary pier; 6. Total station; 7. Level; 8. Upper control computer; 9. Monitor; 10. Pressure sensor; 11. Limit device. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present application.

[0025] Firstly, the embodiments of this application provide a method for on-site weighing of large-segment steel truss girders, which can solve the technical problems existing in the prior art. In order to ensure the completed bridge alignment, the weight of the steel truss girder needs to be accurately controlled. However, when constructing in mountainous canyons, the site is small, the steel truss girder segments are large in size and can weigh hundreds of tons. If the method of obtaining the weight by lifting the whole segment is implemented, the measurement error is large, the lifting equipment cost is high, and the safety risk is high.

[0026] Figure 1 This application provides a schematic flowchart of a real-time monitoring method for on-site weighing of large-segment steel truss girders. Figure 2 A top view of steel truss segment 1 in a real-time monitoring on-site weighing method for large-segment steel truss girders provided in this application embodiment is shown below. Figure 1 , Figure 2 As shown, the on-site weighing method for large-segment steel truss girders under real-time monitoring in this application is as follows: S1: Control multiple jacks 2 located around the bottom of the steel truss segment 1 to perform multiple synchronous lifts. During each synchronous lift, the attitude parameters of the steel truss segment 1 are collected and calculated. Based on the calculation results, the attitude of the steel truss segment 1 is controlled and adjusted. After the attitude parameters are within the allowable deviation range, the next synchronous lift is performed until the steel truss segment 1 is lifted to the predetermined height. During each synchronous lift, if the attitude parameter deviation exceeds the preset alarm threshold range, an automatic warning is issued and the lifting action is stopped. First, it should be noted that after the steel truss beam is assembled on the pedestal, it is pushed along the slide rail to the cantilever end of the assembly platform for subsequent lifting and assembly. Therefore, the weighing process in this case needs to be completed on the pedestal, but the lifting process does not need to be on the pedestal. Therefore, in this case, the aforementioned jacks 2 are arranged around the pedestal, and the pressure sensor 10 is set on the pedestal. The entire weighing process does not require hoisting and transportation, which greatly reduces capital investment and improves weighing efficiency.

[0027] Before weighing, steel truss segment 1 needs to be lifted to a predetermined height to facilitate subsequent lowering for weighing. However, the weight of a single steel truss segment 1 is relatively large, and lifting it to its final position in one go will not only damage the jacks 2, but also, given the large number of jacks 2 and the potential unevenness of the weighing site, it is impossible to guarantee that the tops of multiple jacks 2 will remain on the same horizontal line during the lifting process. This will directly affect the levelness of the steel truss segment 1. If the tilt of the steel truss segment 1 is too large, it will not only pose a risk of tipping over, but also affect the accuracy of the weighing. Therefore, this... The scheme employs a multi-lifting and multi-checking method. Multiple jacks 2 simultaneously lift the steel truss segment 1 to a certain height each time. During this simultaneous lifting, the attitude parameters of the steel truss segment 1 are calculated and checked in real time. Once the attitude parameters of the steel truss segment 1 are within the allowable deviation range, the next simultaneous lifting and check is performed. After a predetermined number of cycles, the steel truss segment 1 reaches the predetermined height and can then begin to be lowered for weighing. If the tilt of the steel truss segment 1 is too large during the simultaneous lifting, an early warning is issued and all actions are stopped.

[0028] S2: Place pressure sensor 10 at the bottom of steel truss segment 1, and unload jack 2 synchronously multiple times until the weight of steel truss segment 1 falls on pressure sensor 10, thus achieving the weighing of steel truss segment 1. To ensure weighing accuracy, multiple pressure sensors 10 are used. The setting position of pressure sensor 10 is selected in advance. After steel truss segment 1 is raised to the predetermined height, pressure sensor 10 is placed at the predetermined position in the gap between steel truss segment 1 and the platform. To ensure the safety of the weighing operation, the descent process of steel truss segment 1 is the same as the lifting process, both of which are configured to descend synchronously multiple times. Multiple jacks 2 are gradually unloaded synchronously until the weight of steel truss segment 1 falls completely on pressure sensor 10, thus achieving the weighing of steel truss segment 1.

[0029] Specifically, step S1 includes: S101: Jacks 2 are placed around the bottom of the steel truss segment 1, and an intelligent hydraulic pump station 4 connected to the cylinders of the jacks 2 is arranged. To ensure uniform force distribution, four jacks 2 are arranged opposite each other around the bottom of the steel truss segment 1. The intelligent hydraulic pump station 4 is connected to the jacks 2 through cylinders, enabling precise control of the lifting and lowering of the jacks 2. The intelligent hydraulic pump station 4 can simultaneously control multiple jacks 2, ensuring they remain synchronized during the lifting process. During the lifting, the hydraulic pressure data of each jack 2 displayed by the intelligent hydraulic pump station 4 is converted into the load value of each jack 2, which is also a reference value for judging whether the steel truss segment 1 is lifted smoothly. That is, if the load value of a certain jack 2 is large, it indicates that the steel truss segment 1 is tilted towards that direction, and this needs to be monitored.

[0030] S102: An auxiliary support 5 is arranged on one side of each jack 2. Figure 3 A schematic diagram of the positions of jack 2 and auxiliary pier 5 in a real-time monitoring method for on-site weighing of large-segment steel trusses provided in this application is shown below. Figure 3 As shown, there are four jacks 2. Each jack 2 has an auxiliary pier 5 on one side. The auxiliary pier 5 is a support pier that works with the jack 2 to replace the pads when the steel truss segment 1 is lifted and lowered, so as to facilitate the calculation and control of the attitude parameters of the steel truss segment 1. The auxiliary pier 5 is located on one side of the jack 2 and also around the platform.

[0031] S103: Based on the predetermined height of the steel truss segment 1, the synchronous lifting height of the jack 2 is preset for each time. The lifting state of the jack 2 is controlled by the intelligent hydraulic pump station 4. The synchronous lifting height and the number of synchronous lifting times are preset in the intelligent hydraulic pump station 4 to control the jack 2 to perform lifting actions.

[0032] S104: The intelligent hydraulic pump station 4 controls multiple jacks 2 to perform multiple synchronous lifting operations at a preset synchronous lifting height. After each synchronous lifting operation, the thickness of the pad on top of the auxiliary pier 5 is increased to support the steel truss segment 1. In the initial state, the height of the auxiliary pier 5 is higher than the height of the jacks 2. At this time, the steel truss segment 1 is supported by the auxiliary pier 5. Then, the jacks 2 perform synchronous lifting and lift the steel truss segment 1 off the top of the auxiliary pier 5. Subsequently, a pad with a thickness consistent with the distance between the bottom of the steel truss segment 1 and the top of the auxiliary pier 5 is placed on the top of the auxiliary pier 5. The supporting body of the steel truss segment 1 is transferred from the jacks 2 to the auxiliary pier 5, and then the next synchronous lifting is performed, and so on.

[0033] Furthermore, before jack 2 begins the formal lifting process, it also includes: Place a pad on top of each jack 2; The intelligent hydraulic pump station 4 controls multiple jacks 2 to perform pre-lifting simultaneously in order to eliminate lifting gaps.

[0034] Before the formal lifting, there may be slight gaps between the bottom of the steel truss segment 1 and the jacks 2. Pre-lifting can eliminate these gaps, ensuring that the jacks 2 are in close contact with the steel truss segment 1, reducing correction and weighing errors. At the same time, pre-lifting can check whether the intelligent hydraulic pump station 4 can synchronously control multiple jacks 2, ensuring that all jacks 2 are under force at the same time, avoiding uneven loading or structural tilting caused by asynchrony.

[0035] Furthermore, in step S1, during each synchronous lifting period, the attitude parameters of steel truss segment 1 are collected and calculated, specifically including: S104: Two target spheres are set as measuring points 3 at the same bolt holes at the ends of the four lower chords of the steel truss segment 1. A total station 6 with automatic aiming function is placed at the designated position. The steel truss segment 1 generally includes two lower chords and other common structural components, which will not be elaborated on here. The lower chords face the platform. To facilitate observation of the measuring points 3 and to facilitate the calculation of the attitude parameters of the steel truss segment 1, in this case, the measuring points 3 are set at the same height from the bottom of the beam on the inner web of the lower chord. A spherical prism is installed at the measuring point 3, and the total station 6 is set up at a position that allows a clear view of all measuring points 3. The target sphere is a spherical prism with a base. The target base is fixed at the measuring point 3, and the target sphere is magnetically attached to the target base. The spherical prism is placed in a bolt hole that is easy to accurately position and has good visibility.

[0036] S105: During each synchronous lifting, the total station 6 acquires the current spatial coordinates of all measuring points 3. The coordinate system of measuring points 3 is established with the steel truss segment 1 after the pre-lifting is completed as the reference. The total station 6 acquires the current spatial coordinates of all measuring points 3 multiple times at predetermined intervals to calculate the attitude parameters of the steel truss segment 1 at the current moment. In conjunction with the above description, a pre-lifting is performed before the formal lifting. During the pre-lifting, the elevation and angle of the steel truss segment 1 may change slightly. Therefore, the coordinate system of measuring points 3 is established with the steel truss segment 1 after the pre-lifting is completed as the reference.

[0037] S106: Transmit the current spatial coordinates of all measuring points 3 to the pre-configured main control unit. The main control unit calculates the attitude of the steel truss segment 1 based on the current spatial coordinates of each measuring point at adjacent times. Based on the current spatial coordinates of all measuring points 3, it calculates the height difference between the ends of the four lower chords of the steel truss segment 1, as well as the inclination angle between adjacent and relative measuring points 3, and obtains the attitude parameters of the steel truss segment 1. The arrangement of the measuring points 3 makes the current spatial coordinates of the measuring points 3 equivalent to the current spatial coordinates of the four apex corners of the steel truss segment 1. By calculating the height difference and inclination angle between adjacent and relative measuring points 3 at the same time, the attitude parameters of the steel truss segment 1 can be obtained.

[0038] Furthermore, the height difference between the ends of the four lower chord members of steel truss segment 1 is calculated as follows: , , ,

[0039] Among them, the four measuring points 3 are, in order, the first measuring point, the second measuring point, the third measuring point, and the fourth measuring point. This indicates the current spatial coordinates of the first measuring point during synchronous lifting. This indicates the current spatial coordinates of the second measuring point during synchronous lifting. This indicates the current spatial coordinates of the third measuring point during synchronous lifting. This indicates the current spatial coordinates of the fourth measuring point during synchronous lifting. The elevation difference between the first and second measuring points. The elevation difference between the second and third measuring points. The elevation difference between the third and fourth measuring points. This represents the elevation difference between the first and fourth measuring points.

[0040] Furthermore, the calculation method for the inclination angle between two adjacent and opposite measuring points 3 of steel truss segment 1 is as follows:

[0041]

[0042]

[0043]

[0044] in, The angle between the first and second measuring points. The angle between the first and third measuring points. The angle between the second and fourth measuring points. The angle between the second and third measuring points is denoted as α.

[0045] Furthermore, in step S1, the attitude of the steel truss segment 1 is controlled and adjusted according to the calculation results to ensure that the attitude parameters are within the allowable deviation range before the next synchronous lifting is performed. When the attitude parameter deviation exceeds the preset alarm threshold, an automatic warning is issued and the lifting action is stopped. The specific steps for determining whether to perform the next synchronous lifting and whether to issue an automatic warning and stop the lifting action include: S107: Based on the truss height, truss width and segment length of the steel beam segment, determine the set value range and alarm threshold range of the attitude parameters of steel truss segment 1. S108: During each synchronous lifting operation, calculate the attitude parameters of steel truss segment 1 and determine: If the calculated attitude parameters of steel truss segment 1 are within the set range, then proceed with the next synchronous lifting. If the calculated attitude parameters of steel truss segment 1 are not within the set value range and are not within the alarm threshold range, the lifting height of each jack 2 will be adjusted accordingly, and the attitude parameters of steel truss segment 1 will be calculated again until the calculated attitude parameters of steel truss segment 1 are within the set value range, and then the next synchronous lifting will be performed. If the attitude parameters of the steel truss segment 1 calculated at the moment are within the alarm threshold range, a warning message will be issued and the lifting action will be stopped.

[0046] There are three possible scenarios for the attitude parameters of steel truss segment 1: If the attitude parameters are correct and no adjustment is needed, the next synchronous lifting can proceed directly. If the attitude parameters have errors but are not within the alarm threshold range, then control one or more jacks 2 to perform independent or synchronous minor lifting to adjust the attitude of steel truss segment 1 to the set value range for the next lifting. If the attitude parameters are within the alarm threshold range, there is a risk of tipping over, and the lifting and weighing work must be stopped, with staff intervening to make adjustments.

[0047] Furthermore, as a preferred embodiment, each jack 2 is also provided with a displacement sensor and a load sensor. The displacement sensor is located at the movable end of the jack 2, and the load sensor is located at the top of the jack 2, for auxiliary monitoring and auxiliary measurement.

[0048] The synchronous lifting action and height of each jack 2 are controlled by the intelligent hydraulic pump station 4. The displacement sensor can detect the actual lifting amount of jack 2 in each synchronous lifting action and compare it with the preset synchronous lifting height for each action. The load sensor can obtain the load of each jack 2 after each synchronous lifting action. A jack 2 with a large load indicates that there may be a tilting of the steel truss segment 1, which makes it easier for the staff to detect abnormalities in time. At the same time, the load sensor can also protect jack 2 and prevent excessive load from causing damage.

[0049] Furthermore, step S2 specifically includes: S201: Place several pressure sensors 10 at predetermined positions at the bottom of steel truss segment 1; S202: Level the multiple pressure sensors 10 and install a limiting device 11 on the top surface of the pressure sensors 10; S203: Jack 2 and auxiliary pier 5 are replaced with pads to unload multiple jacks 2 in stages and synchronously until the weight of steel truss segment 1 falls on pressure sensor 10 and the reading of pressure sensor 10 is recorded. S204: Rotate the pressure sensor 10 around the axis to different angles respectively, and record the pressure sensor 10 reading at the current angle; S205: Based on multiple readings from pressure sensor 10, calculate the average pressure to obtain the weight of steel truss segment 1.

[0050] Figure 4 A schematic diagram illustrating the placement of pressure sensors in a real-time monitoring method for on-site weighing of large-segment steel trusses provided in this application is shown below. Figure 4 As shown, two vertical members are typically provided between the two lower chords of the steel truss segment 1. In one possible implementation, the number of pressure sensors 10 is also four, respectively located at the center points of the two lower chords and the two vertical members. A level 7 is used to measure the elevation data of the four sensors' placement positions on the pedestal, and the lowest points are shimmed to ensure that the top surfaces of the four pressure sensors 10 are on the same horizontal plane, thus ensuring the accuracy of the measurement data. To prevent slippage between the bottom of the steel truss segment 1 and the top surface of the pressure sensors 10, a limiting device 11 is installed on the top surface of the pressure sensors 10 and covered with a rubber pad of the same thickness to prevent slippage of the contact surface and damage to the paint. The specific implementation of the limiting device 11 is not specifically limited in this application; it only needs to be able to limit the lateral displacement between the bottom of the steel truss segment 1 and the top surface of the pressure sensors 10.

[0051] The descent of jack 2 is consistent with the lifting process, cooperating with auxiliary pier 5 to achieve synchronous, staged unloading until the weight of steel truss segment 1 is completely borne by pressure sensor 10. After the readings stabilize, the pressure readings of the four pressure sensors 10 are recorded. To eliminate the influence of sensor directionality, after each measurement, the pressure sensor 10 is rotated 120° around its axis, and three readings are recorded. The average value is taken as the final reading. Due to the inherent bias of the instrument, the pressure sensor 10 is calibrated before weighing. The deviation between the displayed value and the actual loaded value is recorded under different loads. The instrument is calibrated through linear fitting. The beam weight data actually collected on site is further corrected by the calibration results to obtain a more accurate value.

[0052] After data acquisition, jack 2 is used to lift the steel truss segment 1, disengaging it from pressure sensor 10. Once stable, pressure sensor 10 is removed. Then, jack 2 unloads the load, allowing auxiliary pier 5 to bear the pressure on steel truss segment 1. Using the same gradual lifting method, the segment is lowered onto the platform step by step by replacing the pads between jack 2 and auxiliary pier 5. This completes the weighing of one steel beam segment.

[0053] Secondly, this application provides a field weighing system for large-segment steel truss girders to implement the aforementioned field weighing method for large-segment steel truss girders. The system specifically includes: The lifting unit includes several jacks 2 for multiple synchronous lifting operations around the bottom of the steel truss segment 1, and an intelligent hydraulic pump station 4 connected to the hydraulic cylinders of the jacks 2 to control the lifting status of the jacks 2. The monitoring unit includes a total station 6 for acquiring the current spatial coordinates of measuring point 3; Pressure sensor 10, which is used to place at the bottom of steel truss segment 1 after the steel truss segment 1 is lifted to a predetermined height; The main control unit is used to calculate the attitude parameters of the steel truss segment 1 after each synchronous lifting based on the current spatial coordinates of the measuring point 3 obtained by the total station 6. It controls the steel truss segment 1 to be lifted again when the attitude parameters are within the allowable deviation range, until the steel truss segment 1 is lifted to the predetermined height. After the steel truss segment 1 is lifted to the predetermined height, the jack 2 is unloaded synchronously multiple times until the weight of the steel truss segment 1 falls on the pressure sensor 10, thereby realizing the weighing of the steel truss segment 1.

[0054] In one possible implementation, see Figure 2 The main control unit includes a host control computer 8 and a display 9 for displaying data parameters. The pressure values ​​of each jack 2, the lifting displacement values, the current spatial coordinate data of the measuring points 3, and the attitude parameters such as the inclination angle and height difference of the steel truss segment 1 calculated from these are all displayed on the display 9. Based on the monitoring data, the monitoring personnel determine whether the attitude of the steel truss segment 1 meets the conditions and proceed to the next step.

[0055] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0056] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0057] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for real-time monitoring of on-site weighing of large-segment steel truss girders, characterized in that, The on-site weighing method includes: Multiple jacks (2) located around the bottom of the steel truss segment (1) are controlled to perform multiple synchronous lifts. During each synchronous lift, the attitude parameters of the steel truss segment (1) are collected and calculated. The attitude of the steel truss segment (1) is controlled and adjusted according to the calculation results. After the attitude parameters are within the allowable deviation range, the next synchronous lift is performed until the steel truss segment (1) is lifted to the predetermined height. During each synchronous lift, when the attitude parameter deviation exceeds the preset alarm threshold range, an automatic warning is issued and the lifting action is stopped. Place the pressure sensor (10) at the bottom of the steel truss segment (1), and unload the jack (2) multiple times synchronously until the weight of the steel truss segment (1) falls on the pressure sensor (10), thus realizing the weighing of the steel truss segment (1). Among them, the attitude parameters are the height difference between the four apex corners of the steel truss segment (1) and the inclination angle between two adjacent and opposite measuring points (3). Measuring points (3) are provided at the same bolt holes at the ends of the four lower chord members of the steel truss segment (1).

2. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 1, characterized in that, The control involves multiple synchronous lifting operations using multiple jacks (2) located around the bottom of the steel truss segment (1), specifically including: Jacks (2) are placed around the bottom of the steel truss segment (1), and an intelligent hydraulic pump station (4) connected to the cylinder of the jacks (2) is arranged. Auxiliary blocks (5) are arranged on one side of each jack (2); Based on the predetermined height of the steel truss segment (1), the synchronous lifting height of the jack (2) is preset for each time; The intelligent hydraulic pump station (4) controls multiple jacks (2) to perform multiple synchronous lifting operations at a preset synchronous lifting height, and after each synchronous lifting operation, increases the thickness of the pad on top of the auxiliary pier (5) to support the steel truss segment (1).

3. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 2, characterized in that, Before controlling multiple jacks (2) to perform multiple synchronous lifting operations at a preset synchronous lifting height, the following steps are also included: Place a pad on top of each jack (2); The intelligent hydraulic pump station (4) controls multiple jacks (2) to perform pre-lifting synchronously to eliminate the lifting gap.

4. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 3, characterized in that, During each synchronous lifting period, the attitude parameters of the steel truss segment (1) are collected and calculated, specifically including: Two target balls are set as measuring points (3) at the same bolt holes at the ends of the four lower chords of the steel truss segment (1), and a total station with automatic aiming function (6) is placed at the set position. During each synchronous lifting, the total station (6) automatically collects the current spatial coordinates of all measuring points (3), wherein the coordinate system of measuring points (3) is established based on the steel truss segment (1) after the pre-lifting is completed; The current spatial coordinates of all measuring points (3) are transmitted to the pre-configured main control unit. Based on the current spatial coordinates of all measuring points (3), the main control unit calculates the height difference between the ends of the four lower chords of the steel truss segment (1) and the inclination angle between adjacent and opposite measuring points (3), and obtains the attitude parameters of the steel truss segment (1).

5. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 4, characterized in that, The height difference between the ends of the four lower chord members of steel truss segment (1) is calculated as follows: 、 、 、 。 Among them, the four measuring points (3) are, in order, the first measuring point, the second measuring point, the third measuring point, and the fourth measuring point. This indicates the current spatial coordinates of the first measuring point during synchronous lifting. This indicates the current spatial coordinates of the second measuring point during synchronous lifting. This indicates the current spatial coordinates of the third measuring point during synchronous lifting. This indicates the current spatial coordinates of the fourth measuring point during synchronous lifting. The elevation difference between the first and second measuring points. The elevation difference between the second and third measuring points. The elevation difference between the third and fourth measuring points. This represents the elevation difference between the first and fourth measuring points.

6. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 5, characterized in that, The calculation method for the inclination angle between two adjacent and opposite measuring points (3) of a steel truss segment (1) is as follows: in, The angle between the first and second measuring points. The angle between the first and third measuring points. The angle between the second and fourth measuring points. The angle between the second and third measuring points is denoted as α.

7. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 4, characterized in that, The posture of the steel truss segment (1) is controlled and adjusted according to the calculation results to ensure that the posture parameters are within the allowable deviation range before the next synchronous lifting is performed. During each synchronous lifting, if the posture parameter deviation exceeds the preset alarm threshold range, an automatic warning is issued and the lifting action is stopped. The specific execution steps for whether to perform the next synchronous lifting and whether to issue an automatic warning and stop the lifting action include: Based on the truss height, truss width and segment length of the steel truss segment (1), the set range of the attitude parameters of the steel truss segment (1) and the range of alarm thresholds are determined. During each synchronous lifting operation, the attitude parameters of the steel truss segment (1) are calculated and determined: If the attitude parameters of the steel truss segment (1) calculated at the present time are within the set range, then the next synchronous lifting will be carried out. If the current calculated attitude parameters of the steel truss segment (1) are not within the set value range and are not within the alarm threshold range, the lifting height of each jack (2) will be adjusted accordingly, and the attitude parameters of the steel truss segment (1) will be calculated again until the calculated attitude parameters of the steel truss segment (1) are within the set value range, and then the next synchronous lifting will be carried out. If the attitude parameters of the steel truss segment (1) calculated at the moment are within the alarm threshold range, a warning message will be issued and the lifting action will be stopped.

8. The method for on-site weighing of large-segment steel truss girders under real-time monitoring as described in claim 2, characterized in that, The pressure sensor (10) is placed at the bottom of the steel truss segment (1), and the jack (2) is unloaded multiple times synchronously until the weight of the steel truss segment (1) falls onto the pressure sensor (10), thereby achieving the weighing of the steel truss segment (1). Specifically, this includes: Several pressure sensors (10) are placed at predetermined positions at the bottom of the steel truss segment (1). The level (7) is used to level multiple pressure sensors (10), and a limiting device (11) is installed on the top surface of the pressure sensor (10). The jacks (2) and the auxiliary piers (5) are alternately used to unload multiple jacks (2) in stages and at the same time until the weight of the steel truss segment (1) falls on the pressure sensor (10) and the reading of the pressure sensor (10) is recorded. Rotate the pressure sensor (10) around the axis to different angles respectively, and record the pressure sensor (10) readings at the current angle respectively; Based on multiple readings from the pressure sensor (10), the average pressure is calculated to obtain the weight of the steel truss segment (1).

9. A field weighing system for large-segment steel truss girders, used to implement the field weighing method for large-segment steel truss girders with real-time monitoring as described in any one of claims 1 to 8, characterized in that, The on-site weighing system for the large-segment steel truss girder includes: The lifting unit includes several jacks for multiple synchronous lifting operations placed around the bottom of the steel truss segment (1), and an intelligent hydraulic pump station (4) connected to the jack cylinders for controlling the lifting status of the jacks. The monitoring unit includes a total station (6) for acquiring the current spatial coordinates of the measuring point (3); Pressure sensor (10) is used to place at the bottom of steel truss segment (1) after the steel truss segment (1) has been lifted to a predetermined height; The main control unit is used to calculate the attitude parameters of the steel truss segment (1) during each synchronous lifting based on the current spatial coordinates of the measuring point (3) obtained by the total station (6), and to control the steel truss segment (1) to be within the allowable deviation range for the next synchronous lifting until the steel truss segment (1) is lifted to the predetermined height. After the steel truss segment (1) is lifted to the predetermined height, the jack (2) is unloaded synchronously multiple times until the weight of the steel truss segment (1) falls on the pressure sensor (10) to realize the weighing of the steel truss segment (1).

10. The on-site weighing system for large-segment steel truss girders as described in claim 9, characterized in that, The main control unit includes a host control computer (8) and a display (9) for displaying data parameters.

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